Coastal homes lack flood insurance because of maps

Saturday

Oct 22, 2011 at 10:05 PM

Federal maps show long-term risk, not hurricane storm surge scenarios

By KATE SPINNER

Despite the sweeping Gulf of Mexico view from Tony and Kathy Zumbano's ground-level kitchen — and the fact that a hurricane could pummel it with crashing 10-foot waves — the federal government does not consider their home a high flood risk.

In fact, when they bought the Venice beachfront property, their real estate agent told them they were lucky not to need flood insurance.

The reason: The maps underlying the nation's flood insurance program do not account for direct hurricane strikes, which can cause catastrophic flooding. Instead, they rely on the average risk of flooding over a long period.

As a result, tens of millions of people in coastal counties across the nation underestimate the likelihood that their property could be inundated — and the possibility that they could take a huge financial loss or worse — if they base their home insurance or evacuation decisions on the flood maps.

This area saw firsthand the enormous power of storm surge 90 years ago, when an unnamed Category 3 hurricane struck near Clearwater on Oct. 25, 1921, sending 6 feet of water and powerful waves into downtown Sarasota.

More recently, Hurricane Katrina on the northern Gulf coast in 2005, and Ike in Texas in 2008, decimated wide swaths with their destructive surges.

People are essentially on their own to assess their storm surge risk, says Bill Read, director of the National Hurricane Center. Too many assume they will never be in danger of flooding because they misinterpret the federal flood maps.

Yet nothing is being done to change the maps. Federal officials say they are not meant to save lives, but rather to protect high-risk property investments.

To protect lives, scientists give states computer programs that show how high the storm surge could rise under the worst-case scenarios.

But it is up to the states and counties to share the information with residents. Keeping the public informed is complicated because some communities do not want to bring attention to their vulerability, given the potential impact on real estate and business.

"Who's going to tell you you need flood insurance? Not your Realtor, not your city," Read said at a conference earlier this year.

Congress created the National Flood Insurance Program in 1968 to reduce the federal cost of natural flooding disasters. It requires anyone in the 100-year flood plain — an area where the flood risk over a 30-year span is an extraordinary 1 in 4 — to buy flood insurance if they have a federally backed mortgage.

But few outside that defined scenario buy flood insurance, even though the chances of flooding are much greater than the likelihood of fire or many of the other perils covered by standard policies.

Most major floods and storm surges cause significant water damage outside the 100-year floodplain. That gap is demonstrated almost every time a major storm strikes, including during Hurricane Irene, which slammed North Carolina in August.

Irene's flooding from surge and waves caused $2 billion in damage in coastal regions alone, only about 10 percent of which was insured, said Tom Larsen, vice president of Eqecat, a disaster-modeling firm for insurance companies.

For an average 2,000- square-foot home on a concrete slab, an inch of water inside causes $21,000 in damage, according to federal figures.

While a higher elevation may protect against most floods, this is not failsafe protection from storm surge.

Large parts of Venice Beach, Osprey, Nokomis, North Port, downtown Sarasota, and downtown Bradenton are high enough to escape most river and canal flooding from rain. As a result, they are excluded from flood insurance requirements based on flood maps. But they are close enough to the Gulf — or tidal rivers — that a big hurricane hitting at the right angle could push water to windowsills or even rooftops.

Different maps, created by emergency managers, show that risk. The maps identify those vulnerable areas as storm-surge evacuation zones.

About two-thirds of Sarasota County — including most of the land outside the 100-year floodplain — is in a storm-surge evacuation zone.

Southwest Florida's population density, coupled with a shoreline that enhances storm-driven sea level rises, makes this one of the most dangerous places for storm surge.

As a storm nears the coast, seas build, raising water along the shore and in bays and tidal creeks until it surges over any land in its way. The amount of surge depends on the size of the storm, its windspeed, how fast it moves and at what angle it strikes the coast.

The worst surge in Sarasota County would raise seas 35 feet, enough to boost the Myakka River a foot more than 10 miles inland. Such a surge also would innundate downtown Sarasota and North Port.

East of U.S. 41 in South Sarasota County, the neighborhood of Sorrento East seems deceptively isolated from the Gulf. Most of the neighborhood sits outside the 100-year flood plain.

But with Blackburn Bay to the west and tidal South Creek to the north, it would take just a large Category 1 or 2 hurricane to flood every home in the neighborhood. A storm surge of 15 feet is possible in most of the neighborhood with just a Cat 2 storm hitting at a certain angle.

When Pat Trumbette recently bought her home in Sorrento East, her insurance agent recommended flood insurance, partly for that reason.

"I didn't think we needed it," Trumbette said.

Her son-in-law, Patrick Deputy, said he did not believe the area would ever flood — not even his own home on a tidal canal in Sorrento Shores.

"If a direct 5 hits, I guess I'm doomed," Deputy said.

That storm — the most extreme hurricane on the Saffir-Simpson scale — would almost certainly doom Sorrento Shores and Sorrento East.

But even a strong Cat 2, such as Hurricane Ike, could flood perhaps thousands of homes in Southwest Florida — and not just in Sorrento East. Other vulnerable areas include most of Englewood, parts of downtown Sarasota and even parts of Venice east of Interstate 75.

People's conviction that they will never flood is "a major, major situation for Florida," says Donald Cailloutte, an author of hurricane-readiness books and former comprehensive planner for the city of Venice, said.

"People believe they will never flood because they do not need to buy flood insurance," Cailloutte said. "If you get a Category 2, 3, 4 or 5, they could get ruined."

The Sarasota region has not seen significant storm-driven sea level rise in decades.

"Really, Sarasota has been spared for many, many years," said Ed McCrane, director of Emergency Management for Sarasota County.

But it was merely a tropical depression in June 1992 that caused some of the area's worst flooding. The storm dumped 17 to 25 inches of rain across Sarasota and Manatee counties, flooding nearly 4,000 homes. Sixty percent of those homes were not in the high-risk flood zone, said Desiree Companion, flood mitigation specialist for Sarasota County.

In 2004, Hurricane Ivan didn't come within 400 miles of Southwest Florida's coast but increased the water level in Tampa Bay by 3 feet before striking the Panhandle.

The storm deposited a pile of shells on the Zumbanos' walkway to the beach. "He never even made it here, but the water did come up to our property," Tony Zumbano said from his kitchen.

Mary Jane Corless and her husband took the cautious approach when they bought a home in Sorrento East last year.

They learned that their home is an evacuation zone and bought flood insurance, even though it wasn't required.